(1) Field of the Invention
The present invention pertains to a low cost construction of a hand held and hand operated liquid sprayer typically called a trigger sprayer. In particular, the present invention pertains to a double valve element that is employed in the trigger sprayer construction in lieu of two separate valve elements typically employed in prior art trigger sprayer constructions. The double valve element reduces the number of component parts of the trigger sprayer and thereby reduces its cost of manufacturing.
(2) Description of the Related Art
Hand held and hand operated liquid sprayers commonly known as trigger sprayers are well known in the liquid sprayer art. Trigger sprayers are commonly used to dispense household cleaning or cooking liquids in a stream, spray pattern or as a foam. A trigger sprayer is typically connected to a plastic bottle containing the liquid dispensed by the trigger sprayer.
A typical trigger sprayer is comprised of a sprayer housing that is connected to a neck of the liquid containing bottle by either a threaded connection or a bayonet-type connection. The sprayer housing is formed with a pump chamber, a vent chamber, a liquid discharge passage communicating the pump chamber with an outlet orifice of the trigger sprayer and a liquid supply passage communicating the pump with a dip tube that extends into the liquid of the bottle when the trigger sprayer housing is attached to the bottleneck.
A pump piston is mounted in the pump chamber for reciprocating movements of the pump piston between charge and discharge positions relative to the pump chamber. A vent piston is often connected to the pump piston and is mounted in the vent chamber for reciprocating movements of the vent piston between a closed venting position and an open venting position of the vent piston relative to the vent chamber. In the open venting position of the vent piston the interior of the bottle is vented to the exterior environment of the trigger sprayer. In the closed position of the vent piston the vent chamber is sealed and thereby the interior of the bottle is sealed from the exterior environment of the trigger sprayer. A spring is usually provided in the sprayer housing pump chamber for biasing the pump piston and the vent piston toward their respective charge and closed positions.
A trigger is mounted on the sprayer housing by a pivot connection at one end of the trigger. The trigger is also connected to the pump piston and the vent piston. Repeating the sequence of manually squeezing the trigger toward the sprayer housing against the bias of the pump chamber spring, and then releasing the trigger oscillates the trigger about its pivot connection and reciprocates the pump piston between its charge and discharge positions relative to the pump chamber as well as reciprocates the vent piston between its closed and open positions relative to the vent chamber.
A pair of check valves or one-way valves are assembled in the sprayer housing. One of the check valves, often comprised of a ball valve and a ball valve seat, is provided in the sprayer housing between the pump chamber and the liquid supply passage. This ball valve controls the flow of liquid from the dip tube and through the supply passage to the pump chamber and prevents the reverse flow of liquid from the pump chamber to the dip tube. The second check valve, also often comprised of a ball valve and a ball valve seat, is positioned between the pump chamber and the liquid discharge passage and controls the flow of liquid from the pump chamber to the liquid discharge passage and prevents the reverse flow of liquid from the liquid discharge passage to the pump chamber.
A nozzle assembly having a discharge orifice is assembled to the sprayer housing at the outlet of the liquid discharge passage. The liquid discharge passage usually contains a liquid spinner assembly. The spinner assembly has a liquid spinner head at one end adjacent the nozzle orifice.
From the manual oscillating movement of the trigger that reciprocates the pump piston in the pump chamber, the liquid is drawn from the bottle through the dip tube past the first check valve to the pump chamber. The liquid is then pumped from the pump chamber through the liquid discharge passage and the second check valve to the liquid spinner and the discharge orifice and is dispensed from the trigger sprayer.
The typical trigger sprayer described above has several separate component parts that all contribute to the overall cost of manufacturing the trigger sprayer. Because the typical trigger sprayer is manufactured and sold in very large volumes, even the slightest reduction in the manufacturing cost of the trigger sprayer can result in significant overall reductions in the cost of manufacturing of trigger sprayers. Thus, it is desirable to reduce the number of separate component parts of the trigger sprayer to reduce its manufacturing costs
The low cost trigger sprayer of the present invention reduces manufacturing costs by reducing the number of separate component parts that are assembled into the trigger sprayer. More specifically, the low cost trigger sprayer of the invention is constructed with a double valve member, replacing the two separate check valves of the prior art trigger sprayer with a single member that performs the functions of the two prior art check files.
The trigger sprayer has a sprayer housing that is similar to the sprayer housings of prior art trigger sprayers in that it comprises a pump chamber, a vent chamber, a liquid discharge passage and a liquid supply passage. The sprayer housing also has an integral connector cap that attaches the trigger sprayer to a separate bottle containing a liquid to be dispensed by the trigger sprayer. However, the sprayer housing differs from prior art sprayer housings in that a portion of the liquid discharge passage and a portion of the liquid supply passage are formed as a single continuous passage that extends vertically upwardly through the sprayer housing from the bottom of the housing. The top of the continuous vertical passage communicates with the remainder of the liquid discharge passage that extends to the liquid spinner in the sprayer housing.
A nozzle cap is attached to the sprayer housing adjacent the liquid spinner. The nozzle cap has a discharge orifice position adjacent the liquid spinner that discharges the liquid pumped from the bottle by the trigger sprayer.
The pump chamber communicates with the continuous passage through both an inlet passage and an outlet passage. The inlet passage and the outlet passage are spaced from each other along the continuous passage of the sprayer housing. The vent chamber also communicates with the continuous passage of the sprayer housing through a vent passage that communicates the vent chamber with the continuous passage.
The single valve member is inserted into the continuous passage of the sprayer housing and is positioned in the continuous passage between the pump chamber inlet passage and the pump chamber outlet passage. The single valve member has a cylindrical base that seats in the continuous passage of the sprayer housing between the pump chamber inlet passage and the pump chamber outlet passage and divides the continuous passage of the sprayer housing into the liquid discharge passage on one side of the valve member base and the liquid supply passage on the other side of the valve member base. A resilient sleeve or tube valve projects upwardly from the valve member base and engages against the interior surface of the liquid discharge passage covering over the pump chamber outlet passage. Thus, the resilient tube valve functions as the check valve in the liquid discharge passage that allows liquid flow from the pump chamber to the liquid discharge passage but prevents the reverse flow of liquid.
A stem projects downwardly from the center of the valve base and a resilient disk valve is provided on the distal end of the stem. The length of the stem positions the disk valve below the pump chamber inlet passage in the liquid supply passage.
A cylindrical valve seat insert is inserted into the liquid supply passage below the disk valve. The valve seat insert has an annular peripheral surface that seats against a portion of the disk valve adjacent its peripheral surface. An interior bore extends through the valve seat insert and defines a portion of the liquid supply passage. The dip tube is inserted into the valve seat interior bore at the bottom of the valve seat. Thus, the disk valve seating against the annular peripheral surface of the valve seat insert functions as the check valve that allows liquid flow through the dip tube and the liquid supply passage to the pump chamber, but prevents the reverse flow of liquid.
A manual trigger is attached to the exterior of the sprayer housing and is operatively connected to the pump piston and vent piston to cause the pistons to reciprocate through their respective pump chamber and vent chamber on manual manipulation of the trigger. The trigger has a pair of integral spring arms that bias the trigger away from the sprayer housing. The spring arms eliminate the need for a separate coil spring in the sprayer housing. The reciprocation of the pump piston between charge and discharge positions of the pump piston in the pump chamber draws liquid through the dip tube and unseats the disk valve allowing the liquid to be drawn through the liquid supply passage and the pump chamber inlet passage into the pump chamber. Reciprocation of the pump piston also forces the liquid from the pump chamber through the pump chamber outlet passage displacing the resilient tube valve from its engagement with the interior surface of the liquid discharge passage and pumping the liquid through the liquid discharge passage past the liquid spinner and out through the discharge orifice of the sprayer.
The construction of the trigger sprayer described above with the single valve element having both a disk valve to control the liquid drawn into the pump chamber and a tube valve to control the discharge of the liquid from the pump chamber reduces the component parts of prior art trigger sprayers by providing a single valve member with two valve elements. The integral spring arms of the trigger also eliminates the separate spring of the prior art trigger sprayer. The reduction in the number of component parts that go into the assembly of the trigger sprayer reduces its manufacturing costs.